Machines of all types and nature comprise components that rotate at varying speeds and which may vibrate with different amounts of vibration at different rotational speeds. An acceptable amount of component vibration at one speed of rotation, may not be acceptable at other speeds of rotation, while changes in conditions of use and the stability of the machine containing the rotating component add further variation to vibration amounts. There is therefore a continuing need for means for assessing and evaluating vibration with changes in speed of rotation and particularly assessing and evaluating changes in vibration as they might occur under changing conditions subjected upon the rotating component and the machine containing same during use.
Vibrations experienced from rotating components in stationary mounted machinery in a non-moving environment are generally easiest to measure and evaluate, the rotating components being retained under controlled conditions. Machinery contained in moving vehicles adds a level of difficult in ascertaining accurate measurement and evaluation of the rotating components particularly depending upon the environment within which the moving vehicle may be moving.
Vibrations associated with water craft, particularly vibrations in the motorized power train of small and medium sized water craft, are particularly difficult to accurately measure and assess, due to the continuing changing surface of water on which the vessel is traveling, and the interference occasioned by the inconsistent movement of the hull and power train in response to inconsistent wave action during the vessel's travel through water. Thus vibrations which might foretell a potentially serious problem, may be felt only sporadically by a boat operator and in association with particular weather or wave impact and are easily dismissed as environmentally associated, as distinct from potential equipment failure, until failure of the device occurs.
Vibration in a water craft generally starts as a barely distinguishable hum at various vessel speeds and in many instances is perceived by the operator as a comforting sound confirming efficient operation of the vessel at those speeds. Frequently, the hum is not accompanied by a noticeable sense of vibration, particularly when the vessel is crashing through waves so the hull is flexing with the movement of the vessel and the operator is braced to absorb the motion and pounding of movement through the water. If the operator does become uncomfortable with the hum he generally doesn't associate it with equipment failure, but merely accepts same as a characteristic of the speed at which the boat is traveling and generally merely adjusts his speed to avoid the continuation thereof. By the time the hum becomes associated with a problem, the damage has already been done and the small problem which could have been conveniently and inexpensively repaired, becomes a major problem.
Various vibration monitoring means are known in the art, and the effect of changes in vibration of rotating components is a well recognized method of identifying problems associated with rotating component wear before it reaches a critical stage. The significant cost, lack of portability and general necessity that vibration monitoring means of the prior art be operated by highly skilled operators, has generally limited the use of available monitoring devices to periodic checks of large commercial vessels by skilled vibration monitoring services, thus deterring their use in small and medium sized recreational vessels.
In the past, vibration monitoring of water craft has been limited to periodic monitoring services by uniquely skilled personnel who sample vibration data at various fixed rotational speeds while the vessel is either at rest in the water or under very controlled water conditions to establish a base vibration data point. Periodically the sampling is repeated under the same conditions at the same fixed rotational speeds at later times after wear is expected or an increase of vibration has been noticed by the operator of the craft. Each time the operation is undertaken, sophisticated monitors are brought into the vessel and attachments are made to the appropriate stuffing boxes, struts or bearing housings the entire process taking significant time which converts to cost and down time of the vessel.
An object of the present invention is to provide a portable vibration monitoring means and system which can be conveniently installed in a water vessel and operated by a generally non-skilled operator which automatically assess and evaluate discrete vibration sources in the power train of a small water vessel at varying speeds of rotation thereof, and provide continuous status information to the operator.